Observations of Dislocations in Ammonium Dihydrogen Phosphate: Production of Dislocation-Free Crystals

Abstract

The results of etch‐pit and diffraction topographic studies on ammonium dihydrogen phosphate (ADP) are reported. These studies were carried out on specimens sectioned by abrasive wheel and string‐saw from large single crystals grown from aqueous solution. The two characterization methods are shown to be in approximate one‐to‐one correspondence in the case of sections produced by abrasive sawing. Absence of both etch pits and topographic images in sections made by string‐sawing of material well removed from the seed region is taken to indicate that this material is dislocation‐free. Preliminary results on the plasticity of ADP are reported.